What To Think About With New Construction
We use mechanical ventilation to keep the air fresh, heating the incoming air with the exhaust air. And we use dehumidifiers to maintain healthy moisture levels and prevent mold. Then we make sure not to let heat pass through the building’s skin by designing a sealed and insulated building envelope. Not only do the walls, slabs and roof need to be properly insulated, but so do all of the openings. High-quality windows are one of the biggest up-front expenses in a Passive House, but they contribute to a large portion of the energy savings. We can insulate like crazy, but if we use subpar windows, all of the heat will exit through the glass. The building envelope, which is like its skin, is only as strong as its weakest point.
An indoor air quality monitor, like this Awair unit, measures data points like pollution and moisture, and it gives you a qualitative score that you can track via an app on your phone. What can you do as a homeowner? Use your power as a consumer to push for transparency in the process. Get an indoor air-quality monitor, specifically one that measures Particulate Matter PM2.5, such as the Awair monitor and app, pictured here. Splurge on an infrared camera (I like the Flir One, which fits on an iPhone) and look to see where thermal leaks are happening in your thermal envelope. Being involved as an informed client means you have a better sense of the massive amount of information your builder is trying to juggle. Manage your expectations, and prioritize. And remember, all of these principles can be applied to retrofits just as well as new construction. The best way to think about any home-improvement project is to have it be a steppingstone toward a larger goal. If you can afford to take only small steps, just make sure you are making those steps in the right direction so you don’t have to redo or undo work later. For example, the most cost-effective point in time to make renovatio...
3. Remember That Buildings Are for People I always start projects by reminding my clients that buildings are for people. It seems an obvious statement, but somewhere in the discussions about how to meet code, how to meter energy usage and how to stay within budget, we tend to forget that small fact. Americans spend 90 percent of their time in buildings, and at least a third of that is at home in bed. For me and many others who specialize in passive building, the green building movement is not about energy balance. It’s more about health and comfort. Passive design strategies like proper orientation, compactness of form, well-designed shading and high-performing windows can help you conserve before you compensate. Using passive strategies throughout the design process helps streamline the pathway to reaching net-zero (when your home annually produces more than it consumes), because you have less consumption that you need to compensate for with renewables. And along the way, you’re paying attention to health and comfort instead of only the energy balance.
2: The Biggest Bang for Your Buck Is in High-Performance Windows Statistically speaking, if you’re in the U.S., whatever you’re thinking of as a high-performance window is probably not. Historically, American manufacturers have been far behind Europe in the sophistication of available products. That is starting to change, with some truly amazing products now made in the U.S., but you may need to search a little deeper and save in other areas of your build to offset the expense. Instead of spending your budget on systems that compensate for consumption, like larger photovoltaic systems or geothermal heat pumps, you could allocate those funds to better windows that also bring more comfort to your home. Not only do high-performance windows guarantee comfort, they also contribute to a consistent indoor environment, which is easier to ventilate, purify and keep clean and healthy. What can you do as a homeowner? Do your research and prepare yourself mentally. Yes, high-performance windows cost substantially more than code windows, and there’s just no way around that. We need to shift our mentality to think about the entire building assembly as a highly engineered product itself. Invest...
What can you do as a homebuilder? Learn, learn, learn. Continued education in building science can help you get a grip on heat and moisture flows through assemblies. Consider courses like the Certified Passive House Tradesperson workshop, which my colleagues, pictured here, and I put on a few times a year near Denver, and where you can learn about air sealing, moisture management and indoor air quality. The North American curriculum is also licensed to other qualified trainers across the U.S., and builders can express interest in finding a course near them by joining a waitlist for their city.
Also, find out if the house will have a continuous (that part is important) ventilation system, either a heat recovery ventilation (HRV) system or an ethalpic recovery ventilation (ERV) system with at least an 80 percent efficiency rate. An HRV is a simple box involving fans, filters and a heat-recovery core where outgoing air passes incoming air without mixing. In very dry or very humid climates, the best scenario is an ERV, which also balances moisture.
What can you do as a homeowner? Consider a third-party building code, like Passive House, that sets performance criteria above and beyond what your local code requires, based on international best practices. Ask a lot of questions of your professional team involved in your home project. Try to obtain the results of your home’s Blower Door Test, shown here, which should be required in areas meeting the 2015 International Energy Conservation Code. A lower number means it’s more airtight. Code usually requires 3 or 4 ACH50 or less (ACH is air changes per hour during the test, at a pressure of 50 Pascal). Passive homes require 0.6 or less, a drastic difference. Generally speaking, a builder that can build more airtight is often more meticulous with other details as well and will have a higher quality of construction. If your builder doesn’t inspire confidence on these subjects (or even if they do), consider hiring a third-party representative, such as a building science consultant, to advocate for you and help the builder meet the project goals.
1. Building to Code Does Not Eliminate Risk of Moisture Damage or Poor Indoor Air Quality: For example, the most recent versions of energy-efficiency codes have started to require air sealing as a strategy for conserving energy losses. This is a fantastic development in the movement toward consuming less energy, but it has unfortunately left many homes subject to moisture damages due to a lack of understanding about vapor movement and ventilation. A tradesman applies sealing tape to a window install to ensure resiliency against moisture. Air sealing is good. Buildings should not breathe through their walls. The mechanical ventilation system is in charge of this, much like we breathe through our respiratory system, not our skin. Fewer air leaks means better building durability, higher energy efficiency and lower energy bills. With airtightness, however, we need to have a better understanding of moisture control and ventilation to avoid condensation, mold, poor indoor air quality and, eventually, health concerns. Household air pollution was rated the third most significant cause of ill health for the world’s population, according to the World Health Organization. Exposure to poor i...
How to Take Care of Your Neighbors When Building: A few things to include in that first communication: • When the work will begin, how long it is expected to last and what equipment will be used • Whether they will need to move their cars at certain times or if the street will be blocked off at any point • The work schedule you’ve negotiated with your pros — for example, no work before 8 or 9 a.m. or after 4 or 5 p.m. • Assurance that your remodel is legal and will be done with the necessary permits Bring your design plans to help them visualize what the end result will look like. End by asking about and showing respect for their time. If they work from home, have young children who take daytime naps or have other schedule-related concerns, listen and let them know you will do what you can to accommodate them. When to give your neighbors an update: • You’ve learned that the crew will need to close your street on a cert...
Communicate Frequently With Your Team A weekly or biweekly status report can help identify areas of concern. This should be done at the onset of the project and continue through construction. The construction phase is where there are likely to be changes due to site conditions, availability of products or other factors. Be sure to get all changes documented in writing, along with the dollar amount promised; sign off on both the changes and the cost to stay in control and to ensure that all team members are up-to-date at every stage of the building process. In construction the document is usually called a change order; it explains the nature of the change and the cost. Sometimes the changes are called extras, because they are additional to what was agreed on in the construction contract. For example, a homeowner might decide to move the location of a door, so the designer will assess the impact of the change with the general contractor and draw up a change order for review by the client. If the client is OK with the amount, then he or she would ideally sign the physical copy (often confirmation via email is used) and the work would begin.
Drywall is a master of disguise. The walls in this picture look like they could be plaster. One of the visual giveaways that you're actually looking at drywall is when you see the sharp corners created by standard corner bead. Corner bead is a metal or plastic piece that covers the outside corners of drywall to protect them from damage. Then joint compound is spread over the bead and sanded smooth. In many traditional plaster applications, a rounded piece of wood trim was placed at the corners and then plastered over, creating a round corner. To mimic this look with drywall, look for a bullnose corner bead. QuietRock (shown), which is two pieces of gypsum laminated together with a special glue that allows the assembly to absorb sound and make your living space quieter. The drywall is installed with the same special glue at the seams, and a putty-like material is placed around outlet boxes. If installed properly, it is quite effective — but that doesn't come cheap.
1. You’re Building a New Home Constructing a new home is a great opportunity to create proper storage as well as efficient flow, so it’s good to take organizing into account as you plan your project. • Design the flow of your home to work for your lifestyle by considering your daily routines. For instance, consider where you will enter the home, drop off mail and have your children do their homework. • Plan storage to accommodate everyone in the household. Will your family size grow — perhaps with a new baby or an aging parent — or shrink — perhaps with a child going off to college — in the near future? • It’s best to declutter before planning your remodel. That way, you can plan to store what you want to keep rather than what you have now. • Measure your possessions before finalizing storage solutions. For example, if you don’t want your toiletry items on the counter, be sure to select drawers or cabinets with sufficient depth and height to house them. Similarly, if you don’t want all your pots and pans on the stovetop when not in use, be sure your new kitchen cabinets can store them all. • If your remodel or building project requires you to move out temporarily, take the items...
I often describe the building envelope as being like an inflated balloon. One hole in the balloon, and all the air will escape. It doesn’t matter how sturdy the rest of the balloon is. So not only do we want to have a consistently insulated building envelope, but we also want to avoid any air leakages where hot air can escape in the winter or enter in the summer. One way the Passive House standard verifies the absence of air leakages is with the Blower Door Test, in which the entire house is closed up and air is pumped inside. A gauge, shown here, then measures the air-flow rate relative to the volume of the house. Tests like this, along with energy simulations, measure whether a home is built to the Passive House standard.
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